The Linux Foundation provides a hub for open source developers to code, manage, and scale different open technology projects. It also manages the Linux Kernel Organization that exists to distribute various versions of the Linux kernel which is at the core of all Linux distributions, including those used by Oracle Linux. The Linux kernel manages the interactions between the computer hardware and user space applications that run on Oracle Linux.

You must install and run one of these Linux kernels with Oracle Linux:

• Unbreakable Enterprise Kernel (UEK): UEK is based on a stable kernel branch from the Linux Foundation, with customer-driven additions, and several UEKs can exist for a specific Oracle Linux release. Its focus is performance, stability, and minimal backports by tracking the mainline source code provided by the Linux Kernel Organization, as closely as is practical. UEK is tested and used to run Oracle Engineered Systems, Oracle Cloud Infrastructure (OCI), and large enterprise deployments for Oracle customers.

  UEK includes some packages or package versions that aren't available in RHCK. Some examples are btrfs-tools, rds, and rdma related packages, and some kernel tuning tools.

• Red Hat Compatible Kernel (RHCK): RHCK is fully compatible with the Linux kernel that's distributed in a corresponding Red Hat Enterprise Linux (RHEL) release. You can use RHCK to ensure full compatibility with applications that run on Red Hat Enterprise Linux.

Kernel packages are purposely built to avoid dependencies on a particular kernel type. Any kernel that isn't in use can be removed from the system without impact. For example, to remove RHCK from a system that's running UEK, you can run:

sudo dnf remove kernel-core

See Checking Available Kernels on the System to see what kernels are installed on the system.

See Unbreakable Enterprise Kernel documentation for more information about UEK.

For more information about available kernels, see Oracle Linux 8 Kernel Reference